The present invention relates to a printer and a printing method.
Among various kinds of printing technology, there is one which prints a print image on a recording layer of a lens sheet including a lenticular lens in which a large number of cylindrical convex lenses (hereafter, convex lenses) are disposed in parallel (refer to Japanese Patent No. 3,471,930 (paragraphs 0066 to 0076, FIGS. 1, 5, 8, 9 etc.)). In such a printing technology, a large number of striped subdivided images corresponding to a pitch of the convex lenses (a lens resolution) are aligned and recorded on a recording layer of the lens sheet. Then, it is possible, in accordance with a kind of the subdivided images, to configure in such a way that a visible image is stereoscopically viewed and a picture moves when seen from different angles (animation, etc.; referred to as a variable image).
Meanwhile, as a technical detail of printing directly on the lens sheet furnished with the lenticular lenses, there is one which is disclosed in Patent Document 1. In this patent, in order to absorb a fluctuation in the lens resolution which occurs at the time of manufacturing the lens sheet, a configuration is such as to switch between a lens signal obtained by detecting the lenses of the lens sheet and an encoder signal (an ENC signal). The switching enables an ejection of ink droplets in accordance with the lens resolution.
[Patent Document 1] Japanese Patent No. 3,471,930 (refer to paragraphs 0066 to 0076, FIGS. 1, 5, 8, 9 etc.)
Meanwhile, in the technical detail disclosed in the heretofore described Patent Document 1, there is an advantage that the lens resolution can be automatically determined. However, no details of how to automatically determine the lens resolution are disclosed in the heretofore described Japanese Patent No. 3,471,930. Also, no details of how to carry out the switching between the lens signal and the ENC signal are disclosed, either.
At this point, in the event that a current resolution of the lens sheet is recognized in advance by a printer side, it can be used for a subsequent ink droplet ejection control, motor drive control and the like. However, as described heretofore, no specific method for automatically recognizing the lens resolution exists at present. As a method other than automatically determining the lens resolution on the printer side, there is a method by which an evaluation image and the lens sheet are aligned, and a user visually checks how a moiré occurs at that time and the like, thereby determining the lens resolution. However, in the method, as an examination is carried out by hand, there is a problem in that it takes time and effort.
Also, for example, a method can be considered by which information on the lens resolution is obtained on the user side, based on which the user designates the lens resolution. In this case too, in the same way as the method of using the evaluation image, as a manual operation is required, there is a problem in that it takes time and effort. Also, as another method, a method can also be considered by which a number of lens resolutions usable for the printer is limited to one. However, an optimum lens resolution may often differ depending on a type of print contents in a case of a stereoscopic viewing or a like case, a purpose of exhibition (for appreciation or a POP, etc.), a place of exhibition (indoors or outdoors, etc.), and the like. For that reason, in the event that the number of lens resolutions is limited to one, it is impossible to properly respond to a use application of the lenticular lens.
Also, generally, in the printer, a position of a print head is detected based on an ENC signal outputted from a linear encoder and a rotary encoder. Also, in a case of executing a printing on the lens sheet, a timing signal PTS is generated by multiplying the ENC signal and so on and, based on the timing signal PTS, the print head is controlled and driven, forming a desired print image on the lens sheet.
At this point, in Japanese Patent No. 3,471,930, in view of a variation in the lens resolution, the lens resolution is detected, a lens signal corresponding to the relevant lens resolution is formed, and a drive unit such as the print head is driven based on the lens signal, thus executing a printing on the lens sheet. However, in the printer, as the timing signal PTS is generated based on the ENC signal, although a guarantee of proper operation is given for the drive of the print head based on such a timing signal PTS, in a case of driving the print head based on the lens signal, no guarantee of proper operation (operation stability) is given.
For that reason, even though the print head is driven based on the lens signal to execute the printing on the lens sheet, there is a possibility that a problem occurs, such as an operation instability or a deteriorated image quality. No specific means for solving this kind of problem is disclosed even in Japanese Patent No. 3,471,930. With respect to the drive control based on the ENC signal, not only the print head but, in addition, drive means such as a CR motor and a PF motor are also driven and controlled based on the ENC signal.